Beyond Our Borders

Migrating Broad-winged Hawks (photo: David McCauley)

Only 22% of Canadian bird species spend the whole year in Canada. Most others migrate to the United States (33%), to Central America, Mexico and the Caribbean (23%) or to South America (15%). Some travel to Europe or Asia or spend long periods of time at sea (7%).

More than 75% of Canadian bird species spend at least half of the year outside of Canada. When the plentiful food and warm weather of the Canadian summer ends, migratory birds leave for warmer climates. But migration is risky. Travelling hundreds or thousands of kilometres, birds must find food, shelter and safe passage, both en route and at their destinations. They depend on a chain of stopover sites between their breeding habitats and wintering habitats. If habitat is lost or damaged at any one of these points in their annual journey, it can have drastic consequences.

Bird's-Eye View

Bird species that migrate to South America have decreased much more than species that migrate shorter distances.

At every stage of their annual journeys, migratory species must find sufficient habitat and food and avoid numerous hazards, such as pollution, collisions with buildings and towers, severe storms and uncontrolled hunting.

Migratory birds link Canada with other countries. Canadian conservation efforts for migratory birds are most successful when they foster international cooperation and coordination.

Trends

Among species that winter primarily in each of
four major areas, the percentage assessed as “at risk”
by COSEWIC is highest for species migrating farthest,
to South America (click on graphic for table of
associated data).

Species that migrate the farthest—between Canada and South America—are declining much more steeply than species that over-winter closer to their Canadian breeding grounds. Many species over-wintering in the United States, Mexico, Central America and the Caribbean are also declining severely. Only for birds over-wintering in Canada are there more increasing than decreasing species.

Indicators of the average population status of species that primarily winter in four major regions (click on graphic for a larger version and associated data tables)

Threats

The greatest concern for many migratory species is loss of habitat both inside, and increasingly, outside of Canada. With growing development pressures in many countries in the Caribbean, Central and South America, and global demand for products from these countries, natural habitats are rapidly being converted for human use. Agriculture is replacing both natural forests and grasslands. Logging has significantly reduced the forest habitats of Central America and the Caribbean. Beach-tourism and shrimp aquaculture are replacing coastal habitats, including mangroves and salt marshes.

Pollution—oil spills, pesticides, industrial chemicals and heavy metals—degrades the quality of air, water and terrestrial habitats, and may sicken or kill birds. Many toxic pesticides now banned from Canada and the United States are still in widespread use elsewhere.

Collisions with towers, windows, vehicles and power lines kill millions of birds each year as they migrate between breeding and wintering areas.

Uncontrolled hunting and trapping remains a concern for birds in some countries. Many shorebirds are hunted in the Caribbean, while songbirds are trapped for the caged bird trade in many areas.

Climate change will have particularly strong effects on long-distance migrants because changes anywhere along their migration routes can disrupt their life cycle. Mismatches between migration timing and food availability can lead to reduced nesting success. Changing sea levels will flood coastal stopover habitats. More frequent, stronger storms can lead to major mortality on migration.

Canada Warbler populations have declined dramatically over the last 40 years
and the species is now designated by COSEWIC as Threatened. They face threats
at all stages of their life cycle, including changes in Canada’s boreal forests,
mortality risks on migration and loss of habitat in their wintering areas.
Restoring their populations will require concerted effort throughout their range.
(photo: Nick Saunders)

Solutions: International cooperation helps migrating birds

International cooperation at the continental and hemispheric level is needed to ensure that the needs of migratory birds are addressed at all phases of their life cycles. International treaties, such as the Migratory Birds Convention between Canada and the United States and environmental components of free trade agreements, provide a foundation for cooperative conservation activities. Shared expertise and funding support are needed to develop joint programs. BirdLife International brings together non-government organizations throughout the world to develop coordinated conservation agendas. Many successful cooperative programs have been developed, a few of which are highlighted here, but many more similar programs are needed to ensure that birds hatched in Canada can survive their migratory journey and return to breed.

Semipalmated Sandpiper Flock (photo: Mark Peck)

Western Hemisphere Shorebird Reserve Network (WHSRN)

During migration, many shorebird species, such as Semipalmated Sandpipers, concentrate in large numbers at critical stopover sites where they find food to fuel the next stage of their migration. Loss or degradation of any one of these sites can lead to dramatic declines in their populations. The Western Hemisphere Shorebird Reserve Network has, so far, identified and helped conserve over 80 vital stopover, breeding and wintering sites for shorebirds, throughout the Western Hemisphere.

Birding in the Dominican Republic. (photo: GrupoJaragua)

Rural Caribbean: Economic management for birds and people

The Caribbean islands of Cuba and Hispaniola are important stopover or wintering grounds for many migratory birds that breed in Canada. Nature Canada and its regional partners in Haiti, the Dominican Republic and Cuba are working with rural communities to develop economic activities that conserve bird habitat, such as agro-forestry and ecotourism.

Swainson's Hawk (photo: May Haga)

Southern Cone of South America: Alliance for Grasslands

Grassland species, such as the Swainson’s Hawk, that spend the northern winter in the pampas and cerrado of the Southern Cone of South America face ongoing habitat loss, where grasslands are being converted to agriculture, plantations or urban settlements. The Alliance for Grasslands is a collaboration led by BirdLife International partners in Argentina, Brazil, Paraguay and Uruguay. The Alliance is establishing conservation priorities for monitoring and research and working with private landowners to support bird-friendly production within local and traditional cultural frameworks.